Paper machinery



March 18, I952 s. A. STAEGE 2,589,638

PAPER MACHINERY Filed July 19, 1946 2 SHEETS-SHEET l 8 INVENTOR. 3: 1. asn BY W9w 86 WK ATTORNEYS March 18, 1952 s. A. STAEGE 2,589,638

PAPER MACHINERY Filed July 19, 1946 2 SHEETS-SHEET 2 IN V EN TOR.

ATTORNEYS Patented Mar. 18, 1952 PAPER MACHINERY Stephen A. Staege,Hamilton, Ohio, assignor to The Black-Clawson Company, Hamilton, Ohio, acorporation of Ohio Application July 19, 1946, Serial No. 684,980

11 Claims.

This invention relates to paper making, and more particularly to stocksupply systems for paper making machines. This application is acontinuation-in-part of application Serial No. 607,820, filed July 30,1945, for Paper Machinery, now Patent No. 2,540,301 issued February 6,1951 and assigned to the same assignee as this application.

One of the principal objects of this invention is to provide forcontinuous control of the flow conditions of stock approaching theforming member of a paper mechine to avoid abrupt changes in velocity orpressure and to maintain the desired smooth and uniform flow conditionsacross the width of the stock supply substantially continuously to theforming member.

Another object is to provide for dissipating without turbulence thevelocity energy of stock entering the stock inlet passage of a papermachine at high velocity while at the same time avoiding abrupt orsubstantial changes in flow conditions such as might tend to causeflocculation or lump formation.

An additional object is to provide a stock inlet passage for a papermachine adapted to receive stock at high velocity and including aVenturi portion capable of dissipating the velocity energy of the stockwith minimum turbulence and adapted. to supply the stock to the formingmember in substantially uninterrupted flow without the formation ofpools or slow moving reservoirs of stock tending to cause abrupt orsubstantial changes in the flow conditions.

It is also an object of this invention to provide a stock supply systemfor a paper machine wherein optimum flow conditions may be maintained inthe stock inlet passage over a wide range of speeds of the formingmember.

A further object is to provide a stock supply system for a paper machinewherein the volume of flow of the stock at the slice may be readilyvaried over a wide range while maintaining substantially uniform flowconditions through the stock inlet.

Another object is to provide a stock supply system wherein the flow ofstock into the inlet passage may be at a substantially higher velocitythan at its point of delivery to the forming member in order to maintainthe stock in properly mixed condition and to prevent the heavierconstitutents from settling out even when the machine is operated atcomparatively low speed.

Other objects and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the .appendedclaims.

In the drawings- Fig. 1 is a schematic view of a circulating and stocksupply system in accordance with the invention for a cylinder type papermachine, showing the path of flow of incoming stock and collected whitewater as supplied to and discharged from the paper forming parts;

Fig. 2 is a fragmentary view similar to Fig. 1 showing a stock supplysystem in accordance with the invention for a Fourdrinier type machine;and

Fig. 3 is a view similar to Fig. 1 showing a stock supply system inaccordance with the invention for a Fourdrinier type machine andincluding a by-pass connecting the inlet passage or head box with thesuction side of the circulating pump to control the volume at the slice.

Referring to the drawings, which show preferred embodiments of theinvention, in Fig. ,1 the vat is indicated generally by the referencecharacter l0 and includes the vat circle II with the rotary formingmember or cylinder mold 12 mounted therein. A tapered vat inlet 15supplies the incoming stock to the vat, as described in more detailhereinafter, and the usual mold slice l6 and adjustable rotary slice [1may be provided as desired. The vat has an overflow compartment 20, withthe overflow dam being lowered or removed when using the means formaintaining the vat level described in the above noted applicationSerial No. 607,820.

The white water is withdrawn from vat I0 through pickup 22 located inthe vat, and it is fed through conduit 23 into white water pump 24, newstock from the regulating box being introduced into conduit 23 from pipe25 directly ahead of pump 24 as shown. The level in the vat ismaintained by the white water spill dam 26 shown in dotted lines in Fig.1, the overflow from which may be discharged to the sewer as indicatedat 27.

The discharge of the white water pump is supplied through conduit 30 toa suitable screen 32, the reject from which is removed as shown at 33and discharged. The screened stock is withdrawn through conduit 36 anddelivered into the conduit 31 which also receives the overflow from theoverflow compartment 20, a branch conduit 38 also being provided forreturn of a portion of the white water directly into the stock overflow.Control of flow from overflow compartment 20 is provided by a butterflyvalve t0, and provision is made for power operation of this valve, suchmechanism being shown as comprising a reversible electrical motor 4|operatively connected to cause rotation of the valve by belt or sprocket42. Automatic control of the operation of this motor may in turn beprovided by means such as the liquid level control shown in detail insaid application Serial No. 607,820, such control being effective tomove the valve to a more open position when the liquid within the vatrises above the desired 3 level and to move the valve to a more closedposition when the liquid within the vat falls below the desired level.

A circulating pump 45 delivers the stock from conduits 36 and 31 througha conduit 46 which is preferably branched at 41 to supply the stock to acounterfiow inlet 50, shown as of the construction disclosed in PatentNo. 2,347,717 assigned to the same assignee as this application.

' Within this inlet 50 is a pair of oppositely tapered,

transversely extending conduits and 52 separated by a vertical baffle 54positioned immediately below and parallel to a common discharge orifice55 which is substantially narrower than the corresponding dimensions ofthe tapered conduits 5 i52 and extends transversely across substantiallythe entire width of the inlet passage 15. The branched'conduits 4!supply stock to the larger end of each of these tapered conduits, andthere is thus provided a cross flow of stock through orifice 55 whichgives substantially uniform pressure and flow of stock at relativelyhigh velocity into the inlet passage 15 and across its entire width.

As a result of the restricted dimensions of the discharge orifice 55with respect to the tapered conduits 5l-52, there is during operation asubstantial presure differential across this orifice which develops adefinite velocity condition in the fiow of stock therethrough, thisvelocity flow providing for thorough mixing and distribution of thestock and high uniformity across the entire width of the inlet passage.It is desirable to maintain the pressure differential and velocity offlow substantially uniform across the passage for maximum uniformity ofsheet formation, and also to dissipate the initial velocity energy ofthis stock before it reaches the forming member in order to avoidobjectionable turbulence tending to non-uniform sheet formation.Accordingly, the present invention provides for obtaining these resultsby means of the tapered construction of the inlet passage 15, which isshown as formed to coact with orifice 55 in the manner of a Venturi.

In Fig. l the counterfiow inlet passage 55 is shown as positioned withits discharge orifice 55 spaced at'a substantial distance from the pointof delivery of stock to the forming member l2, thus providing forsubstantial travel of stock between the orifice 55 and the formingmember.

The portion of the inlet l5 adjacent the discharge orifice 55, i. e. thelower portion 60 as shown in Fig. 1, has its walls GI and 62 relativelydiverging away from the discharge orifice and at a relatively smallangle, this angle being not more than about and a satisfactory examplebeing a total included angle of the order of 7 /2" or an increase ofapproximately A per inch of travel. This tapered construction providesfor gradually and progressively increasing the cross-sectional area toat least approximately four times the total area of the dischargeorifice 55. The remaining portion 65 of the inlet passage [5 is shown asgenerally of at least as great cross-sectional area as the larger orupper end of the tapered passage portion 66, this portion 65 beingsmoothly curved to direct the stock from the tapered passage portion tothe slice and the forming zone of the forming member with minimumturbulence or pockets where stock could collect and fiocculate to form alumpy condition.

With the above construction, the stock entering the inlet passage l5through the discharge orifice 55 with a relatively high velocity of flowhas its velocity energy gradually absorbed and dissipated within thetapered Venturi passage portion 66 with minimum turbulence. At the sametime, the construction of the adjacent passage portion 55, which isshown as of substantially the same capacity as the larger end of theVenturi portion 60, provides for directing the stock is a smooth andsubstantially uninterrupted flow directly to the forming zone withoutthe formation of pools or slow moving reservoirs of stock such as maycause abrupt or substantial changes in flow conditions with resultingtendency toward flocculation and lump formation. With this stock supplysystem as shown and described, control over the flow of stock ismaintained continuously from the entry of the stock by way of thedischarge orifice 55 throughout the length of the inlet passage 15 andup to as close to the actual forming zone as is practicable. All thestock between orifice 55 and the forming member is kept in constantmotion towards the forming member at a velocity which is constant acrossthe width of the'inlet passage, changes in velocity being substantiallyuniform laterally and taking place smoothly and with minimum turbulence.

Fig. 2 illustrates an inlet passage similar to that shown in Fig. 1 asapplied to a Fourdrinier type paper machine. In this construction, theforming wire 10 travels over a breast roll H, and stock is suppliedthrough the slice or orifice 15, the width of which may be adjustedvertically by the adjusting mechanism indicated generally at E6. Forwardand backward adjustment of the slice may similarly be made by theadjusting mechanism indicated generally at 11.

In Fig. 2, the stock is supplied to the slice and forming member througha counterfiow inlet 85 and tapered inlet passage in substantially thesame manner as shown and described in connection with Fig. 1. The inletincludes tapered conduits 8| and 82,, a bafile 84 and arestricteddischarge orifice 85 common to both of the tapered conduits. Stock issupplied to the larger end of each of these tapered conduits, asdescribed in connection with Fig. 1, through branched conduits indicatedfragmentarily at 86. The inlet passage includes a portion 96 constructedsimilarly to the portion 60 as described in connection with Fig. 1 andproviding a Venturi passage adapted to receive the stock enteringthrough the orifice 85 and to dissipate the velocity energy thereof asthe stock is transmitted to the slice. The remaining portion 9! of theinlet passage is curved, as shown, to convey the stock from the taperedportion directly to the slice and forming Wire in a substantiallyuninterrupted flow and with minimum turbulence. A rotating perforatedcylinder may be positioned as indicated adjacent the slice, and thestock flows through this cylinder to assure that the fibers will beproperly dispersed throughout the water as the stock passes through theslice onto the forming wire.

The operation of the construction shown in Fig. 2 is substantially thesame as described in connection with Fig. 1 with respect tocontrol ofthe flow of stock between the counterfiow inlet 80 and the formingmember. The stock is initially supplied through conduit 86 undersufficient pressure to provide a flow through orifice 85 at a definiteand substantially uniform velocity across the width of the inletpassage. As this stock enters the Venturi portion 90'of the inletpassage, the progressively increasing capacity of the passage providesfor dissipating the velocity energy of the stock smoothly and withminimum turbulence. The curved passage portion 9| provides for directingthe stock in smooth and continuous flow to and through the rotatingperforated cylinder 05 and into the forming zone itself. Thisconstruction of controlled flow passage avoids formation of pools orslow moving reservoirs of stock capable of causing abrupt changes inflow velocity and thus facilitates maintaining the proper smoothness ofthe stock and freedom from lumps. As in the case of the constructionshown in Fig. 1, the changes in velocity conditions are uniformlaterally and take place smoothly throughout the entire extent of theinlet passage, thus greatly contributing to maximum uniformity of sheetformation.

Fig. 3 illustrates a stock supply system similar to that of Fig. 1 butapplied to a Fourdrinier type paper machine and embodying means forvarying the volume of flow of the stock to the forming member whilemaintaining optimum flow conditions through the orifice of thecounterflow inlet. In Fig. 3, the forming wire I travels over breastroll HM, and the white water draining from the forming wire is collectedin the wire pit or other collecting trough I02 and flows through a pipeI03, joining with new stock supplied through pipe IM from a suitableregulator box, to a circulating pump I05 such as a centrifugal pump. Theresulting stock mixture is supplied through a, pipe I06 to a suitablescreening machine 101, the flow through pipe I06 being shown ascontrolled by a suitable valve I08. From the screening machine the stockflows through conduit I09 to a counterfiow inlet III) similar inconstruction and operation to the counterfiow inlet 50 shown anddescribed in connection with Fig. 1. The stock discharged through thedischarge orifice III of inlet IIO passes through a stock inlet passagesimilar to that shown in Fig. 2 and including a tapered Venturi portionII2, contiguous with orifice III, and a curved portion I I3 whichcooperate to convey the stock as described in connection with Fig. 2directly to the slice M5, the latter being provided with adjusting meansI I0 and II! similar to those shown in Fig. 2.

As was explained in connection with Fig. l, the counterfiow inlet H0 ispreferably operated under pressure conditions such that the flow ofstock through the restricted discharge orifice I I i is at a definitevelocity, these conditions having been found to give satisfactoryresults from a standpoint of thorough mixing of the stock and uniformdistribution and velocity across the entire width of the inlet passage.The optimum flow conditions for a particular inlet of this type willdepend upon the particular design and construction of the inlet, but ingeneral it has been found that if such velocity is varied over anyconsiderable range, the preferred uniform conditions may not bemaintained. On the other hand, it is desirable from the standpoint ofproper control of sheet formation that the volume of flow of the stockthrough the slice be properly correlated with the speed of the formingmember. Furthermore, it is sometimes found desirable or necessary tovary quite widely both the speed of a given machine and the volume offlow of the stock at the slice, but with the inlet designed to giveoptimum results over particular range of flow rates, if the velocityfalls substantially below the preferred range, some settling out of theheavier constituents may occur, particularly in the case of stockcontaining substantial quantities of clay or other types of loadingmaterial, with resulting departure of the sheet characteristics fromthose desired. The present invention accordingly provides control meanssuch that the velocity at the inlet I I0 may be maintained within therange giving optimum uniformity of flow even though the volume of flowof the stock through the slice I i 5 may be very much lower.

In accordance with the invention, these results are obtained with theconstruction shown in Fig. 3 by drawing off from the inlet passagesuiiicient stock to reduce the volume at the slice to a value such thatthe desired volume of flow is obtained. As shown in Fig. 3, there isprovided a slot I20 positioned between the Venturi portion I I2 of theinlet passage and the slice, and this slot extends completely across thewidth of the lowest side of the inlet passage parallel to the slice. Aheader I2 I is positioned below slot !20 and in direct communicationtherewith, this header being of large enough cross-section, as shown, toprovide that the pressure differential across slot I20 will besubstantially the same throughout the width of the inlet passage inorder that the amount of stock withdrawn from the passage will be thesame across its width, thus assuring uniform lateral pressure at theslice. Header I2I is in turn provided with one or more pipes I22bypassing the slice and connecting with pipe I03 on the suction side ofpump I05 as shown. The connection from pipes I22 to header I2I may bemade at one or both ends of the header, or in some cases at severalpoints in addition to the two ends, as maybe found desirable to maintainthe proper uniform pressure differential across slot I20 as stated.Regulating means such as a valve I25 may also be provided forcontrolling the flow through pipe I22 in accordance with the pressureconditions to be maintained at the slice.

With this construction as shown, when the valve I25 is closed, all thestock transmitted by the inlet IIO will be conveyed through the inletpassage iI2I I3 to the slice and forming member, substantially asdescribed in connection with Fig. 2. Similar continuously uniformcontrol over flow conditions will be afforded as with the constructionshown in Fig. 2, and regulation of flow conditions within the rangegiving preferred results may be readily attained by varying the speed ofpump I05 or by throttling its discharge through pipe I06 betweenthe pumpand screening machine. In this manner, the volume of flow of the stockthrough the slice may be readily controlled over a substantial range.

The by-pass construction illustrated in Fig. 3 affords alternative orsupplemental control over fiow conditions, both independently of therate of flow through the inlet passage, with the latter being maintainedat its optimum value, and also in conjunction with the above describedcontrol to adapt the system to even wider ranges of speeds and rates offlow. Thus for a given speed or rate of delivery of pump I05, resultingin a uniform flow rate through the inlet, as valve I25 is opened. stockwill be drawn off uniformly across the width of inlet passage, and therate of flow of the remainder of the stock will be correspondinglyreduced through the slice. This control may be readily obtainedautomatically, by operation of valve I25 through automatic level orpressure control means such as the type shown in the above notedapplication Serial No. 607,820.

As an example of the degree of control and range of conditions affordedby the above con.- struction, the volume range through a typicalcounterfiow inlet of the illustrated construction could be varied in theratio of two to one with little difiiculty, and if desired probably overa range of three to one or even somewhat greater. By the use of therecirculation principle of this invention, however, the range of volumeof flow at the slice could be extended to six to one or evenconsiderably higher while still maintaining only a relatively smallchange in the inlet flow volume such as two to one, thus assuring bestoperating results.

It will accordingly be seen that the present invention provides a stocksupply system for a paper machine of either the cylinder or Fourdriniertype, wherein the control over the flow conditions is continuousthroughout the system and also highly uniform laterally throughout theinlet passage and substantially continuously up to the forming zone. Inthis supply system, the flow of stock into the inlet passage may be atcontrolled velocity to assure uniform mixing and distribution, and thevelocity energy of this velocity stock is smoothly absorbed anddissipated before it reaches the forming zone, thus avoiding turbulenceand abrupt velocity changes tending to produce flocculation or lumpformation. It also provides for readily varying the flow conditionsthroughout the supply system, and particularly for uniform control overthe volume of flow through the slice over a wide range while maintainingoptimum flow conditions elsewhere in the system.

Reference is made to my copending application Serial No. 780,456, filedOctober 1'7, 1947, and assigned to the same assignee as thisapplication.

While the forms of apparatus herein described constitute preferredembodiments of the invention, it is to be understood that the inventionis not limited to these precise forms of apparaus, and that changes maybe made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

1. In a stock supply system for a paper making machine including aforming member, the combination of means forming a slot orificeextending across the full width of said machine, means for dischargingstock through said orifice at a definite and substantially uniformvelocity and with substantially uniform distribution of fiber across theentire extent of said orifice, a chamber corresponding in width to thatof said orifice and of substantially greater cross-sectional area thansaid orifice from which the stock is delivered directly onto saidforming member, and walls forming an inlet passage connecting saidorifice with said chamber to conduct said stock from said orifice tosaid chamber, said passage being of substantially the same width as saidorifice and said forming member, said passage walls diverging at apredetermined small angle in the direction of flow from said orifice toprovide with said orifice a Venturi passage for dissipating with minimumturbulence the velocity energy of said stock entering said passagethrough said orifice, said diverging passage continuing withsubstantially undiminished effective flow area up to said chamber fordelivery of said stock to said chamber with minimum turbulence andflocculation, and said angle of divergence between said passage wallsbeing not more than 10 to maintain said stock between said orifice andsaid chamber in continuous advancing motion to said forming member atadecelerating velocitywhich is sub stantially constant across eachcross-sectional area of said passage.

2. In a stock supply system for a paper making machine including aforming member, the combination of means forming a slot orificeextending across the full width of said machine, means for dischargingstock through said orifice at a definite and substantially uniformvelocity and with substantially uniform distribution of fiber across theentire extent of said orifice, a

chamber corresponding in width to that of said orifice and ofsubstantially greater cross-sectional area than said orifice from whichthe stock is delivered directly onto said forming member, and wallsforming an inlet passage connecting said orifice with said chamber toconduct said stock from said orifice to said chamber, said passage beingof substantially the same width as said orifice and said forming member,said passage Walls diverging at a predetermined angle of not more than10 to maintain said stock between said orifice and said chamber incontinuous advancing motion to said forming member at a deceleratingvelocity which is substantially constant across each cross-sectionalarea of said passage, said passage continuing with substantiallyundiminished effective flow area up to said chamber for delivery of saidstock to said chamber with minimum turbulence and flocculation.

3. In a stock supply system for a paper making machine including aforming member, the combination of means forming a slot orificeextending across the full width of said machine, means for dischargingstock through said orifice at a definite and substantially uniformvelocity and with substantially uniform distribution of fiber across theentire extent of said orifice, a chamber corresponding in width to thatof said orifice and of substantially greater cross-sectional area thansaid orifice from which the stock is delivered directly onto saidforming member, and walls forming an inlet passage connecting saidorifice with said chamber to conduct said stock from said orifice tosaid chamber, said passage being of substantially the same width as saidorifice and said forming member, said passage walls diverging at a totalincluded angle of approximately 7%? in the direction of flow from saidorifice to provide with said orifice a Venturi passage for maintainingsaid stock between said orifice and said chamber in continuous advancingmotion to said forming member at a decelerating velocity which issubstantially constant across each cross-sectional area of said passage,said diverging passage continuing with substantially undiminishedeffective flow area up to said chamber for delivery of stock to saidchamber with minimum turbulence and flocculation.

4. In a paper machine having a forming member and provided with a stockinlet including a pair of oppositely tapered cross flow conduitsarranged in side by side relation and having a common restricteddischarge orifice extending across the full width of said machinethrough which the stock is discharged at a definite and substantiallyuniform velocity and with substantially uniform distribution of fiberacross the entire extent of said orifice, the combination of a chambercorresponding in width to that of said orifice and.

of substantially greater cross-sectional area than said orifice fromwhich the stock is delivered directly onto said forming member, andwalls forming an inlet passage connecting said orifice with said chamberto conduct said stock from said orifice to said chamber, said passagebeing of substantially the same width as said orifice and said formingmember, said passage walls diverging at a predetermined small angle inthe direction of flow from said orifice to provide with said orificeaVenturi passage for dissipating with minimum turbulence the velocityenergy of said stock entering said passage through said orifice, saiddiverging passage continuing with substantially undiminished effectiveflow area up to said chamber for delivery of said stock to said chamberwith minimum turbulence and flocculation, and said angle of divergencebetween said passage walls being not more than 10 to maintain said stockbetween said orifice and said chamber in continuous advancing motion tosaid forming member at a declerating velocity which is substantiallyconstant across each cross-sectional area of said passage.

5. In a stock supply system for a paper making machine including aforming member, the combination of a stock inlet passage leading to saidforming member and of substantially the same width as said formingmember throughout the entire length thereof, means including a conduithaving a discharge orifice extending across the entire width of saidmachine for supplying stock to said inlet passage at a pressure andunder fiow distribution conditions providing a flow of stock throughsaid orifice into said passage at a definite and substantially uniformvelocity across the width of said passage and with substantially uniformdistribution in said stock flow as delivered through said passage tosaid forming member, the walls of said passage diverging at an angle ofnot more than 10 in the direction of flow therethrough to maintain saidstock between said orifice and said forming member in continuousadvancing motion to said forming member at a decelerating velocity whichis substantially constant across each cross-sectional area of saidpassage and to deliver said stock to said forming member in a smoothflow and with minimum turbulence, and means for drawing off stock fromsaid inlet passage at a position downstream in the direction of flowfrom said energy dissipating means to said forming member and spacedupstream from the point of delivery of said stock to said forming memberto reduce the volume of flow of said stock delivered to said formingmember while maintaining a higher velocity flow of stock through saidorifice to maintain said uniform fiow and distribution conditionstherein.

6. In a stock supply system for a paper making machine including aforming member, the combination of a pair of oppositely tapered conduitsarranged transversely across said machine and each adapted to besupplied at the larger end thereof with stock under pressure, meansforming a slot orifice common to said pair of conduits and extendingacross the full width of said machine through which said stock isdischarged from said conduits at a predetermined velocity of flow andwidth substantially uniform distribution of fiber across the width ofsaid machine, said orifice being of restricted cross-sectional arearelative to said conduits to maintain said predetermined velocitysubstantially higher than the velocity of flow of said stock in saidconduits and substantially uniform across the width of said machine,means adjacent said forming member forming a chamber corresponding inwidth to said orifice and of substantially greater crosssectional. areathan said slot orifice, and walls forming an inlet passage ofsubstantially the same width of said orifice and said forming member forconducting stock from said orifice to said chamber, said walls beingarranged to diverge at a predetermined total included angle of not morethan 10 in the direction of flow of said stock from said orifice to saidchamber to maintain said stock between said orifice and said chamber incontinuous motion towards said forming member at a decelerating velocitywhich is substantially constant across each cross-sectional area of saidpassage and to dissipate with minimum turbulence the velocity energy ofsaid stock as said stock fiows from said orifice to said chamber whilemaintaining substantial uniformity of fiow conditions in said stockacross the width of said machine.

7. In a stock supply system for a paper making machine including aforming member, the combination of a pair of oppositely tapered conduitsarranged transversely across said machineand each adapted to be suppliedat the larger end thereof with stock under pressure, means forming aslot orifice common to said pair of conduits and extending across thefull width of said machine through which said stock is discharged fromsaid conduits at a predetermined velocity of flow and with substantiallyuniform distribution of fiber across the width of said machine, saidorifice being of restricted cross-sectional area relative to saidconduits to maintain said predetermined velocity substantially higherthan the velocity of fiow of said stock in said conduits andsubstantially uniform across the width of said machine, means adjacentsaid forming member forming a chamber corresponding in width to saidorifice and of substantially greater cross-sectional area than said slotorifice, and walls forming an inlet passage of substantially the samewidth of said orifice and said forming member for conducting stock fromsaid orifice to said chamber, said walls being arranged to diverge at atotal included angle approximately 7 in the direction of flow of saidstock from said orifice to said chamber to dissipate with minimumturbulence the velocity energy of said stock as said stock flows fromsaid orifice to said chamber while maintaining substantial uniformity offlow conditions in said stock across the width of said machine.

'8. In a stock supply system for a paper machine of the cylinder typeincluding a forming member and a vat in which the forming memberoperates, the combination of a pair of oppositely tapered conduitsarranged transversely across said machine and each adapted to besupplied at the larger end thereof with stock under pressure, meansformin a slot orifice common to said pair of conduits and extendingacross the full width of said machine through which said stock isdischarged from said conduits at a predetermined velocity of flow andwidth substantially uniform distribution of fiberacross the width ofsaid machine, said orifice being of restricted cross-sectional arearelative to said conduits to maintain said predetermined velocitysubstantially higher than the velocity of flow of said stock in saidconduits and substantially uniform across the width of said machine, andwalls forming an inlet passage of substantially the same width as saidorifice and said vat for conducting stock from said orifice to said vat,said walls being arranged to diverge at a predetermined total includedangle of not more than 10 in the direction of fiow of said stock fromsaid orifice to said chamber to maintain said stock between said orificeand said vat in continuous motior towards said vat at a deceleratingvelocity which is substantially constant across each cross-sectionalarea of said passage and to dissipate with minimum turbulence thevelocity energy of said stock as said stock fiows from said orifice tosaid vat while maintaining substantial uniformity of flow conditions insaid stock crosswise of said passage and throughout substantially theentire length thereof.

9. In a stock supply system for a Fourdrinier paper machine including aforming member, the combination of a pair of oppositely tapered conduitsarranged transversely across said machine and each adapted to besupplied at the larger end thereof with stock under pressure, meansforming a slot orifice common to said pair of conduits and extendingacross the full width of said machine through which said stock isdischarged from said conduits at a predetermined velocity of fiow andwith substantially uniform distribution of fiber across the width ofsaid machine, said orifice being of restricted cross-sectional arearelative tosaid conduits to maintain said predetermined velocitysubstantially higher than the velocity of flow of said stock in saidconduits and substantially uniform across the width of said machine,means adjacent said forming'member'forming a closed chambercorresponding in width' to said orifice and of substantially greatercross-sectional area than said slot orifice,and walls forming a totallyenclosed inlet passage of substantially the same width of said' orificeand'said forming member for conducting stock from said orifice to saidchamber, said' passage being of substantially the same cross-sectionalarea as said chamber at the point of connection thereof to said chamber,said walls being arranged to diverge at a predetermined total includedangle of not more than in the direction of flow of said stock from saidorifice to said chamber to maintain said stock between said orifice'andsaid chamber in continuous motion towards said forming member at adecelerating velocity which is substantially constant across eachcross-sectional'area of said passage and to dissipate with minimumturbulence the velocity energy of said stock as said stock flows fromsaid orifice to said chamber while maintaining substantial uniformity offlow conditions in said stock across the width of said passage oversubstantially the entire length thereof.

10; A stock supply system for a paper making machine including a formingmember, comprising a stock inlet passage leading to said forming memberand of-substantiallv the same width as said forming member throughoutthe entire lengththere'ofimeans forming a restricted intake orificeextending across the entire width of said inlet passa e, supplv meansincludin a pump for dischar ing stock throu h said orifice at a definitevelocity providing substantially uniform distribution in said stockacross the width of said passa e, said passa e being of substantiallength between said orifice and said forming member. the-wallsof saidassa e diver ing away from said orifice in the direction of flowtherethrough at an an leof not more than 10 to eifect progressiveincrease of the cross-sectional area of said passa e-with respect tosaid orifice and to eifect absorption of t e velocitv ener y of saidstock discharged through said orifice with deliverv of said stock tosaid forming mem'oer in a smooth flow and with minimum turbulence, saidinlet passage having a slot extending across substantially the entirewidth of the lower side thereof at a position spaced downstream fromsaid orifice in the direction of flow to said forming member and spacedupstream from the point of delivery of said stock to said formingmember, a header positioned below said slot to receive stock flowingfrom said passage through said slot, a pipe for conducting stock fromsaid header to the suction side of said pump to reduce the volume ofstock at said forming member while maintaining said definite velocity offlow and uniform distribution of said stock through said orifice, andmeans for regulating the flow of stock through said pipe to maintain apredetermined volume of stock at said forming member.

11. A stock supply system for a paper making machine including a formingmember, comprising a stock'inlet passage of substantial length leadingto said forming member and of substantially the same width as saidforming member, a plurality of oppositely tapered cross flow conduitsarranged transversely of said inlet passage and having a commonrestricted discharge orifice arranged longitudinally thereof to providecommunication from ,both' thereof across substantially the entire widthof said passage, a pump for supplying stock'to each of said conduits ata pressure sufiicient to effect a flow of stock through said orifice ata definite velocity providing substantially uniform distribution in saidstock across the width of said' passage, the walls of said passagediverging away from said orifice at an angle of not more than 10 andcooperating therewith to provide a 'Venturi passage adapted to receivesaid stock from'said orifice and to dissipate the velocity energythereof with minimum turbulence, said passage continuing withsubstantially undiminished effective flow area from said orifice to saidforming member to convey said stock in substantially uninterrupted flowfrom said orifice to said forming member, said inlet passage having aslot extending across substantially the entire width of the lower sidethereof at a position spaced downstream in the direction of flow fromsaid Venturi passage and spaced upstream from the point of delivery ofsaid stock to said forming member, means for conducting stock from saidslot to the suction side of said pump to reduce the volume of fiow ofsaid stock to said forming member while maintaining said definitevelocity flow and uniform distribution of stock through said orifice,and means for regulating said flow of stock through said slot tomaintain a predetermined volume of stock adiacent said forming member inaccordance with the speed thereof.

STEPHEN A. STAEGE.

REFERENCES CITED The following references are of record in the file ofthis patent:

. UNITED STATES PATENTS Number

